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High Power Mode-Locked Semiconductor Lasers and Their Applications

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High Power Mode-Locked Semiconductor Lasers and Their Applications University of Central Florida STARS Electronic Theses and Dissertations, 2004-2019 2008 High Power Mode-locked Semiconductor Lasers And Their Applications Shinwook Lee University of Central Florida Part of the Electromagnetics and Photonics Commons, and the Optics Commons Find similar works at: https://stars.library.ucf.edu/etd University of Central Florida Libraries http://library.ucf.edu This Doctoral Dissertation (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Electronic Theses and Dissertations, 2004-2019 by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation Lee, Shinwook, "High Power Mode-locked Semiconductor Lasers And Their Applications" (2008). Electronic Theses and Dissertations, 2004-2019. 3722. https://stars.library.ucf.edu/etd/3722 HIGH POWER MODE-LOCKED SEMICONDUCTOR LASERS AND THEIR APPLICATIONS by SHINWOOK LEE B.Sc. Sogang University, Republic of Korea, 1993 M.Sc. Sogang University, Republic of Korea, 1995 A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Optics and Photonics/CREOL at the University of Central Florida Orlando, Florida Spring Term 2008 Major Professor: Peter J. Delfyett, Jr. © 2008 Shinwook Lee ii For My Mother and Wife. iii ABSTRACT In this dissertation, a novel semiconductor mode-locked oscillator which is an extension of eXtreme Chirped Pulse Amplification (XCPA) is investigated. An eXtreme Chirped Pulse Oscillator (XCPO) implemented with a Theta cavity also based on a semiconductor gain is presented for generating more than 30ns frequency-swept pulses with more than 100pJ of pulse energy and 3.6ps compressed pulses directly from the oscillator. The XCPO shows the two distinct characteristics which are the scalability of the output energy and the mode-locked spectrum with respect to repetition rate. The laser cavity design allows for low repetition rate operation <100MHz. The cavity significantly reduces nonlinear carrier dynamics, integrated self phase modulation (SPM), and fast gain recovery in a Semiconductor optical Amplifier (SOA). Secondly, a functional device, called a Grating Coupled Surface Emitting Laser (GCSEL) is investigated. For the first time, passive and hybrid mode-locking of a GCSEL is achieved by using saturable absorption in the passive section of GCSEL. To verify the present limitation of the GCSEL for passive and hybrid mode-locking, a dispersion matched cavity is explored. In addition, a Grating Coupled surface emitting Semiconductor Optical Amplifier (GCSOA) is also investigated to achieve high energy pulse. An energy extraction experiment for GCSOA using stretched pulses generated from the colliding pulse semiconductor mode-locked laser via a chirped fiber bragg grating, which exploits the XCPA advantages is also demonstrated. Finally, passive optical cavity amplification using an enhancement cavity is presented. In order to achieve the interferometric stability, the Hänsch-Couillaud Method is employed to stabilize the passive optical cavity. The astigmatism-free optical cavity employing an acousto- iv optic modulator (AOM) is designed and demonstrated. In the passive optical cavity, a 7.2 of amplification factor is achieved with a 50 KHz dumping rate. v ACKNOWLEDGMENTS First of all, I would like to thank to my adviser, Prof. Delfyett, who has introduced the world of ultrafast optics. Personally and scientifically, I have learned a lot of things from him. His positive attitude and strong enthusiasm for life is also what I would like to earn during my Ph.D course. I have enjoyed a supportive atmosphere of the ultrafast group in CREOL. It was fortunate for me to have such supportive and good colleagues. They are Prof. Sangyun Gee, Dr. Michael Mielke, Dr. Tolga Yilmaz, Dr. Myoung Taek Choi, Dr. Kyungbum Kim, Dr. Wangkuen Lee, Dr. Luis Archundia, Dr. Bojan Resan, Dr. Nishant Bhatambrekar, Franklyn Quinlan, Sarper Ozharar, Ji- Myoung Kim, Mr. Dimitrios Mandridis, Ibrahim Ozdur, Mohammad Umar Piracha, Charles Williams, Iffat Nayyar, Sharad Bhooplapur, Abhijeet Ardey, Henock Legesse, Dat Nguyen, Nazanin Hoghooghi, Josue Davila-Rodriguez, Sen-Yong Chen and my lab mate, Dimitrios Mandridis. I express my sincere thanks to all of professors in CREOL and staffs for establishment of such a solid structure of photonics research. Especially, I also want to acknowledge my committee members for this dissertation, who are Prof. Likamwa, Prof. Riza, and Prof. Kapoor. Finally, I dedicate this dissertation to my wife, Kyunglae Kang, and my mother, Chiae Kim. Without their prayer and love, this dissertation could not have been done. vi TABLE OF CONTENTS ABSTRACT................................................................................................................................... iv ACKNOWLEDGMENTS ............................................................................................................. vi TABLE OF CONTENTS.............................................................................................................. vii LIST OF FIGURES ....................................................................................................................... xi LIST OF TABLES.....................................................................................................................xviii LIST OF ACRONYMS/ABBREVIATIONS.............................................................................. xix CHAPTER 1 INTRODUCTION .................................................................................................... 1 1.1 Semiconductor gain media .................................................................................................... 1 1.1.1 Semiconductor laser........................................................................................................ 1 1.1.2 Semiconductor optical amplifiers ................................................................................... 4 1.2 Carrier dynamics of semiconductor gain media.................................................................... 7 1.3 Semiconductor mode-locked lasers..................................................................................... 11 1.3.1 Active mode-locking..................................................................................................... 13 1.3.2 Passive and hybrid mode-locking ................................................................................. 14 1.4 Scope and organization of the dissertation.......................................................................... 17 CHAPTER 2 EXTREME CHIRPED PULSE AMPLIFICATION.............................................. 20 2.1 High power semiconductor mode-locked laser ................................................................... 20 2.2 Concept of extreme chirped pulse amplification................................................................. 21 2.3 Colliding pulse semiconductor mode-locked laser.............................................................. 23 2.4 Chirped fiber bragg grating for XCPA................................................................................ 32 2.5 Extreme chirped pulse amplification system....................................................................... 34 vii 2.6 Summary.............................................................................................................................. 37 CHAPTER 3 EXTREME CHIRPED PULSE OSCILLATOR BASED ON THETA CAVITY DESIGN.................................................................................................................................. 39 3.1 A more of extreme chirped pulse amplification .................................................................. 39 3.2 Preliminary experiment for extreme chirped pulse oscillator ............................................. 41 3.3 Theta cavity design for extreme chirped pulse oscillator.................................................... 45 3.4 Extreme chirped pulse oscillator for > 1ns stretched pulses ............................................... 55 3.4.1 Theta cavity and experimental setup............................................................................. 56 3.4.2 Experimental results...................................................................................................... 62 3.5 Amplification of stretched pulses from the XCPO.............................................................. 69 3.6 <100MHz repetition rate operation of the Theta cavity ...................................................... 74 3.7 Preliminary experiment of feed forward intensity noise cancellation and gain flattening scheme for frequency swept pulses ..................................................................................... 78 3.8 Summary.............................................................................................................................. 80 CHAPTER 4 GRATING COUPLED SURFACE EMITTING LASER AND GRATING COUPLED SURFACE EMITTING SEMICONDUCTOR OPTICAL AMPLIFIER ........... 82 4.1 Introduction ......................................................................................................................... 82 4.2 Grating coupled surface emitting laser................................................................................ 85 4.3 Passive and hybrid mode-locking of grating coupled surface emitting laser...................... 89 4.3.1 Experimental setup for mode-locking..........................................................................
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